Hydraulic arrangement for vertically trimming a marine propulsion unit

ABSTRACT

Disclosed herein is a marine propulsion device, such as an outboard motor, including a transom bracket adapted to be attached to a boat transom, a swivel bracket pivotally connected to the transom bracket about a generally horizontal axis and having a vertically extending bore including a cylindrical portion, a propulsion unit including a housing supporting a propeller, a king pin having a length greater than the bore, and fixedly connected, at its upper and lower ends, to the housing and extending through the bore, a piston on the king pin in engagement with the cylindrical bore portion, means in the bore above the piston supporting the king pin for axial and rotative movement relative to the swivel bracket and for sealing an upper part of the bore against loss of hydraulic fluid, means in the bore below the piston for supporting the king pin for axial and rotative movement relative to the swivel bracket and for sealing a lower part of the bore against loss of hydraulic fluid, a pair of spaced hydraulic conduits extending through the swivel bracket and respectively communicating with the bore above and below the piston, and means communicating with the conduits for selectively supplying hydraulic fluid to the bore through one of the conduits and simultaneously draining hydraulic fluid from the bore through the other of the conduits.

[ 1 Feb. 27, 1973 United States Patent 1 Blanchard [54] HYDRAULIC ARRANGEMENT FOR VERTICALLY TRIMMING A MARINE PROPULSION UNIT [75] Inventor: Clarence E. Blanchard, Kenosha,

Wis.

bracket pivotally connected to the transom bracket about a generally horizontal axis and having a vertically extending bore including a cylindrical portion, a propulsion unit including a housing supporting a propeller, a king pin having a length greater than the bore, and fixedly connected, at its upper and lower ends, to the housing and extending through the bore, a piston on the king pin in engagement with the cylindrical bore portion, means in the bore above the piston supporting the king pin for axial and rotative moven .m t a m 0 C m 8 Mn I17 9 1 dm .558 e 18 .M J ma wm OWS Me 0 W N l m w A FA H MH 7 22 I52] lLS. Cl. HT, ll5/l7 [58] Field of suarchnml 15/4] HT, 41 R 17. 18,34 ment relative to the swivel bracket and for sealing an upper part of the bore against loss of hydraulic fluid, means in the bore below the piston for supporting the king pin for axial and rotative movement relative to [5 6] References Cited the swivel bracket and for sealing a lower part of the bore against loss of hydraulic fluid, a pair of spaced hydraulic conduits extending through the swivel UNITED STATES PATENTS f R X bracket and respectively communicating with the bore Kiebler ct 15/4 R x above and below the piston, and means communicat- Kiekhaefer"....................l15/41 R X 334 555 999 lll II/ 354 939 961 184 337 222 ing with the conduits for selectively supplying hydraulic fluid to the bore through one of the conduits and simultaneously draining hydraulic fluid from the bore through the other of the conduits.

Primary ExaminerMilton Buchler Assistant Examiner-Carl A. Rutledge Att0rneyRobert E. Clemency et al.

9 Claims, 2 Drawing Figures 1 M W 7 Z a w a "W1. 3 a "M I Wi /1w HYDRAULIC ARRANGEMENT FOR VERTICALLY TRIMMING A MARINE PROPULSION UNIT BACKGROUND OF THE INVENTION The invention relates to marine propulsion devices, such as outboard motors and stem drive units, and particularly to such marine propulsion devices which are employed for racing. Still more particularly, the invention relates to hydraulic arrangements for raising and lowering the propulsion unit of such a marine propulsion device so as to regulate or trim the location of the propeller relative to the water. One example of such a prior hydraulically operated arrangement is disclosed in the US. Kiekhaefer Pat. No. 2,674,219 issued Apr. 6, 1954.

SUMMARY OF THE INVENTION The invention provides an arrangement adapted for hydraulically raising and lowering a steerable marine propulsion unit, including a driving propeller, relative to a supporting boat and therefor relative to the water, said arrangement including an elongated king pin which is connected at its upper and lower ends to the propulsion unit for common steering movement, which extends through spaced upper and lower bushings seated in the bore of a swivel bracket to define therebetween a hydraulic cylinder, and which includes a piston operable in the cylinder defined between the upper and lower bushings. Also provided in the swivel bracket are spaced upper and lower conduits which communicate with the cylinder on opposite sides of the piston and with an electrically powered reversible combination motor and pump unit which is selectively operable to simultaneously supply pressure fluid to one side of the piston and afford drainage of hydraulic fluid from the other piston side, and vice versa. Preferably, the conduits communicates with the cylinder through means defined by the upper and lower bushings.

One of the principal objects of the invention is the provision of a marine propulsion device comprising means for hydraulically vertically lifting a steerable propulsion unit and including an elongated king pin which is connected at both its upper and lower ends to the steerable propulsion unit.

Another of the principal objects of the invention is the provision of a marine propulsion device comprising means for hydraulically vertically lifting a propulsion unit in such manner as to prevent unwanted upward movement and so as to positively regulate the location of the propulsion unit relative to the boat.

Another of the principal objects of the invention is the provision of an arrangement for hydraulically regulating the height of a propulsion unit relative to a supporting boat, which arrangement is economical to manufacture and which will provide reliable operation over a long and useful life, notwithstanding the severe service which occurs during racing events.

Other objects and advantages of the invention will become known by reference to the following description and accompany drawings.

Drawings FIG. 1 is a perspective view of a marine propulsion device which is in the form of an outboard motor and which embodies various of the features of the invention.

FIG. 2 is an enlarged fragmentary view, partially in section and partially schematic, of the marine propulsion device shown in FIG. 1.

Before explaining the invention in detail, it is to be understood that the invention is not limited in its application to the details of construction and arrangement of parts set forth in the following general description or illustrated in the accompanying drawings, since the invention is capable of other embodiments and of being practiced or carried out in various ways. Also, it is to be understood that the phraseology or terminology employed herein is for the purpose of description and not of limitation.

GENERAL DESCRIPTION Shown in FIGS. 1 and 2 is a marine propulsion device 11 such as, for instance, an outboard motor, which device embodies various of the features of the invention and which includes a first or transom bracket 13 adapted to be fixed to a boat transom 17 Pivotally connected to the transom bracket 13 about a generally horizontal axis 19 is a second or swivel bracket 21 which includes a bore 23 extending generally perpendicularly to the horizontal tilt axis 19, i.e., generally vertically when the transom bracket 13 is attached to the boat transom l7.

Extending through the swivel bracket bore 23 is a king pin 27 which is fixed at its upper and lower endsto a propulsion unit 29 including a housing 31 supporting a propeller 33. The king pin 27 can be fixed rigidly to the housing 31 or can be connected to the housing 31 through resilient mounts as is well known in outboard motor constructions. The upper end of the king pin 27 is also rigidly connected to a steering arm 37 operable to effect steering movement of the king pin 27 and connected propulsion unit 29. As thus far described, the construction is entirely conventional.

In accordance with the invention, and in order to afford controlled vertical adjustment of the assembly of the king pin 27 and propulsion unit 29 relative to the boat transom 17, the king pin 27 is substantially elongated relative to the height of theswivel bracket 21. In addition, the swivel bracket bore 23 includes a cylindrical portion 39 and the king pin 27 is provided with a piston 41 engaged with the cylindrical bore portion 39. Still further in addition, means are provided above the piston 41 in the bore 23 for supporting the king pin 27 for axial and rotative movement relative to the swivel bracket 21 and for sealing an upper part of the bore 23 against loss of hydraulic fluid. Still further, means are provided in the bore 23 below the piston 41 for supporting the king pin 27 for axial and rotative movement relative to the swivel bracket 21 and for sealing a lower part of the bore 23 against loss of hydraulic fluid.

Still further, means are provided for selectively and simultaneously supplying hydraulic oil to the bore 23 on one side of the piston 41 and withdrawing or draining oil from the bore 23 on the other side of the piston 41, and vice versa. In this regard, there is provided, in the disclosed construction, an electrically operated, reversible combination motor-pump unit 43 which communicates with a pair of upper and lower spaced conduits 47 and 49, respectively, located in the swivel bracket 21 and respectively communicating with the bore 23 above and below the piston 41. The combination motor-pump unit 43 preferably is mounted in the boat hull, although the unit 43 could also be mounted exteriorly of the boat hull and, for instance, on the rear of the transom 17. Various well known electrically operated reversible combination motor-pump units can be employed.

More particularly and further in accordance with the invention, the means in the bore 23 above the piston 41 for sealing the upper end of the bore 23 and for rotatably and axially supporting the king pin 27 includes an upper bushing 51 which includes a bore or aperture 52 receiving the king pin 27 and which is seated in the bore 23. Any suitable means, such as a snap ring 54 engaged in the bore 23 above the upper bushing 51, can be employed to prevent outward expulsion of the upper bushing 51 from the bore 23 under the action of hydraulic pressure.

The upper bushing 51 also includes a first external annular groove 53 receiving an O-ring 57 which provides a seal between the upper bushing 51 and the king pin 27 and an internal annular groove 59 including an O-ring 61 which provides a seal between the upper bushing 51 and the king pin 27.

Also in accordance with the invention, the means in the bore 23 below the piston 41 includes a lower bushing 63 which is seated against a shoulder 67 in the bore 23, and which includes a bore or aperture 64 receiving the king pin 27 and an outer annular groove 69 housing an O-ring 71 providing a seal between the lower bushing 63 and the swivel bracket 21. The lower bushing 63 also includes an inner annular groove 73 containing an O-ring 77 providing a seal between the king pin 27 and the lower bushing 63. The vertical spacing between the upper and lower bushings 51 and 63 defines a hydraulic cylinder in which the piston 41 is operable.

While other construction are possible, in the construction illustrated in the drawings, the swivel bracket bore 23 includes, in addition to the cylindrical portion 39, a second or intermediate portion 79 which is located immediately below the cylindrical portion 39 and which receives the lower bushing 63, and a third or lower portion 81 located below the second portion. In addition, the swivel bracket bore 23 includes a shoulder 83 between the cylindrical portion 39 and the second portion 79, which shoulder 83 is adapted to be engaged by the piston 41 when the king pin 27 and connected propulsion unit 29 are in their lowermost position, thus also providing a seat, independent of the bushings, for supporting the propulsion unit in the absence of hydraulic fluid in the cylinder. Still further,

the swivel bracket bore 23 includes the previously mentioned shoulder 67 which is located between the intermediate portion 79 and the lower portion 81 and which forms a seat for the lower bushing 63.

Also in accordance with the invention and as shown in the specifically illustrated construction, the king pin 27 includes adjacently located first, second, and third portion 89, 91, and 93 respectively. The upper or first portion 89 has a diameter corresponding to the bore 52 in the upper bushing 51. The second or intermediate portion 91 has a diameter less than the upper portion 89 and is threaded to receive thereon the piston 41. The third or lower portion 93 has a diameter smaller than the second portion 91 and is received in the bore 64 of the lower bushing 63. If desired, the third or lower portion 93 of the king pin 27 can extend through a lower bearing 97 provided directly by the swivel bracket 21 or otherwise.

As is a common construction, the piston 41 includes an external groove 121 housing an O-ring 123 preventing hydraulic fluid flow from one side to the other of the piston 41.

Also in accordance with the invention and as already mentioned, there is provided, in the swivel bracket 21, spaced upper and lower hydraulic conduits 47 and 49. The upper hydraulic conduit 47 communicates with an external groove 125 which is located in the upper bushing 51 below the annular groove 53 and which communicates with an axial slot 129 communicating with the bore 23 below the upper bushing 51 and above the piston 41. The lower conduit 49 communicates with a chamfered recess 133 along the upper outer margin or periphery of the lower bushing 63, which recess 133 communicates with the bore 23 above the lower bushing 63 and below the piston 41.

Accordingly, when the king pin 27 and connected propulsion unit 21 are in their lowermost position with the piston 41 seated on the shoulder 83 and located adjacent to the lower bushing 63, hydraulic oil under pressure supplied to the annular recess 133 through the lower conduit 49 will be effective to raise the piston 41 and king pin 27, and thereby also to raise the propulsion unit 29. At the same time, oil above the piston will be withdrawn through the upper conduit 47 When it is desired to lower the king pin 27 and connected propulsion unit 29, the combination motor-pump unit 43 is operated to supply pressure fluid to the bore 23 through the upper conduit 47 and to afford withdrawal of pressure fluid from the bore 23 through the lower conduit 49.

From the foregoing, the propulsion unit 29 can be raised as desired by supplying pressure fluid to the bore 23 through the lower conduit 49 and withdrawing fluid from the bore 23 through the upper conduit 47. In addition, the propulsion unit 29 can be lowered by permitting withdrawal of pressure fluid from the bore 21 below the piston 41 through the lower conduit 49 and by supplying pressure fluid to the bore 23 above the piston 41 through the upper conduit 47 Complete control of the vertical location of the propulsion unit 29 is thereby obtained, i.e., unwanted movement of the propulsion unit 29, either up or down, relative to the swivel bracket is thereby prevented, while simultaneously there is hydraulically afforded selective adjustment of the height of the propulsion unit 29 relative to the swivel bracket 21.

Although he invention has been illustrated and described in connection with an outboard motor, various of the features of the invention are also applicable to stem drive units.

Various of the features of the invention are set forth in the following claims.

What is claimed is:

l. A marine propulsion device including a first bracket adapted to be attached to a boat transom, a second bracket pivotally connected to said first bracket about an axis which is generally horizontal when said first bracket is attached to the boat transom, said second bracket having a bore extending generally perpendicularly to said axis and including a cylindrical portion, a propulsion unit including a housing supporting a propeller, a king pin having a length substantially greater than said bore and fixedly connected at its upper and lower ends to said housing and extending through said bore, a piston on said king pin in engagement with said cylindrical bore portion, means in said bore above said piston for supportingsaid king pin for axial and rotative movement relative to said second bracket and for sealing an upper part of said bore against loss of hydraulic fluid, means in said bore below said piston for supporting said king pin for axial and rotative movement relative to said second bracket and for sealing a lower part of said bore against loss of hydraulic fluid, a pair of spaced hydraulic conduits extending through said second bracket and respectively communicating with said bore above and below said piston, and means communicating with said conduits for selectively supplying hydraulic fluid to said bore through one of said conduits and simultaneously draining hydraulic fluid from said bore through the other of said conduits.

2. A marine propulsion device in accordance with claim 1 wherein said means in said bore above said piston includes a bushing surrounding said king pin and seated in said bore, means for providing a seal between said bushing and said bore, and means for providing a seal between said king pin and said bushing.

3. A marine propulsion device in accordance with claim 1 wherein said means in said bore below said piston includes a bushing surrounding said king pin and seated in said bore, means providing a seal between said bushing and said bore, and means providing a seal between said king pin and said bushing.

4. A marine propulsion device in accordance with claim 1 wherein said bore includes an annular shoulder which is located at the lower end of said cylindrical portion and which is adapted to be engaged by said piston when said king pin is in its lowermost position.

5: A marine propulsion device in accordance with claim 1 wherein said means for selectively supplying and draining hydraulic fluid includes an electrically powered combination reversible motor-pump unit communicating with said conduits.

6. A marine propulsion device in accordance with claim 1 wherein said means in said bore above said piston includes an upper bushing having therein an aperture, wherein said means in said bore below said piston includes a lower bushing having therein an aperture, wherein said king pin includes axially adjacent first, second, and third portions with said first portion being received in said lower bushing aperture and having a diameter less than said second portion, wherein said second portion has a diameter less than said third portion and includes a screw thread, wherein said third portion is received in said upper bushing aperture, and wherein said piston is screwed on said second portion thread.

7. A marine propulsion device in accordance with claim 1 wherein said means in said bore above said piston includes a bushing having a passageway communicating with one of said conduits and with the interior of said cylindrical portion below said bushing.

8. A marine propulsion device in accordance with claim 1 wherein said means in said bore below said piston includes a bushirig having a passageway commuconduits and with the interior nicating with one of sai of said cylindrical portion above said bushing.

9. An outboard motor comprising a transom bracket adapted to be attached to a boat transom, a swivel bracket pivotally connected to said transom bracket about an axis which is generally horizontal when said transom bracket is attached to the boat transom, said swivel bracket having a bore extending generally perpendicularly to said axis and including a cylindrical portion, a first annular shoulder located at the lower end of said cylindrical portion, and a second annular shoulder located in spaced relation below said first annular shoulder, a propulsion unit including a housing supporting a propeller, a king pin having a length substantially greater than said bore and including an upper portion, an intermediate portion extending from said upper portion and having a diameter less than said upper portion and including a screw thread, and a lower portion extending from said intermediate portion and having a diameter less than said intermediate partition, said king pin extending through said swivel bracket bore and being fixedly connected, at its upper and lower ends, to said housing, a piston screwed on said intermediate king pin portion and located in engagement with said cylindrical bore portion and adapted to engage said first annular shoulder when said king pin is in its lowermost position, an upper bushing seated in said bore above said piston and supporting said king pin for axial and rotative movement relative to said swivel bracket, said upper bushing having a bore receiving said upper king pin portion and an external groove communicating with said bore below said upper bushing, means providing a seal between said upper bushing and said bore, means providing a seal between said king pin and said upper bushing, a lower bushing seated in said bore below said piston and against said second annular shoulder and supporting said king pin for axial and rotative movement relative to said swivel bracket, said lower bushing having a bore receiving said lower king pin portion and means defining an external recessed area along the upper outer periphery of said lower bushing, means providing a seal between said lower bushing and said bore, means providing a seal between said king pin and said lower bushing, an upper hydraulic conduit extending through said swivel bracket and communicating with said external groove in said upper bushing, a lower hydraulic conduit extending through said swivel bracket and communicating with said recessed area defined by said lower bushing, and an electrically powered reversible combination motor-pump unit communicating with said conduits for selectively supplying hydraulic fluid to said bore through one of said conduits and simultaneously draining hydraulic fluid from said bore through the other of said conduits. 

1. A marine propulsion device including a first bracket adapted to be attached to a boat transom, a second bracket pivotally connected to said first bracket about an axis which is generally horizontal when said first bracket is attached to the boat transom, said second bracket having a bore extending generally perpendicularly to said axis and including a cylindrical portion, a propulsion unit including a housing supporting a propeller, a king pin having a length substantially greater than said bore and fixedly connected at its upper and lower ends to said housing and extending through said bore, a piston on said king pin in engagement with said cylindrical bore portion, means in said bore above said piston for supporting said king pin for axial and rotative movement relative to said second bracket and for sealing an upper part of said bore against loss of hydraulic fluid, means in said bore below said piston for supporting said king pin for axial and rotative movement relative to said second bracket and for sealing a lower part of said bore against loss of hydraulic fluid, a pair of spaced hydraulic conduits extending through said second bracket and respectively communicating with said bore above and below said piston, and means communicating with said conduits for selectively supplying hydraulic fluid to said bore through one of said conduits and simultaneously draining hydraulic fluid from said bore through the other of said conduits.
 2. A marine propulsion device in accordance with claim 1 Wherein said means in said bore above said piston includes a bushing surrounding said king pin and seated in said bore, means for providing a seal between said bushing and said bore, and means for providing a seal between said king pin and said bushing.
 3. A marine propulsion device in accordance with claim 1 wherein said means in said bore below said piston includes a bushing surrounding said king pin and seated in said bore, means providing a seal between said bushing and said bore, and means providing a seal between said king pin and said bushing.
 4. A marine propulsion device in accordance with claim 1 wherein said bore includes an annular shoulder which is located at the lower end of said cylindrical portion and which is adapted to be engaged by said piston when said king pin is in its lowermost position.
 5. A marine propulsion device in accordance with claim 1 wherein said means for selectively supplying and draining hydraulic fluid includes an electrically powered combination reversible motor-pump unit communicating with said conduits.
 6. A marine propulsion device in accordance with claim 1 wherein said means in said bore above said piston includes an upper bushing having therein an aperture, wherein said means in said bore below said piston includes a lower bushing having therein an aperture, wherein said king pin includes axially adjacent first, second, and third portions with said first portion being received in said lower bushing aperture and having a diameter less than said second portion, wherein said second portion has a diameter less than said third portion and includes a screw thread, wherein said third portion is received in said upper bushing aperture, and wherein said piston is screwed on said second portion thread.
 7. A marine propulsion device in accordance with claim 1 wherein said means in said bore above said piston includes a bushing having a passageway communicating with one of said conduits and with the interior of said cylindrical portion below said bushing.
 8. A marine propulsion device in accordance with claim 1 wherein said means in said bore below said piston includes a bushing having a passageway communicating with one of said conduits and with the interior of said cylindrical portion above said bushing.
 9. An outboard motor comprising a transom bracket adapted to be attached to a boat transom, a swivel bracket pivotally connected to said transom bracket about an axis which is generally horizontal when said transom bracket is attached to the boat transom, said swivel bracket having a bore extending generally perpendicularly to said axis and including a cylindrical portion, a first annular shoulder located at the lower end of said cylindrical portion, and a second annular shoulder located in spaced relation below said first annular shoulder, a propulsion unit including a housing supporting a propeller, a king pin having a length substantially greater than said bore and including an upper portion, an intermediate portion extending from said upper portion and having a diameter less than said upper portion and including a screw thread, and a lower portion extending from said intermediate portion and having a diameter less than said intermediate partition, said king pin extending through said swivel bracket bore and being fixedly connected, at its upper and lower ends, to said housing, a piston screwed on said intermediate king pin portion and located in engagement with said cylindrical bore portion and adapted to engage said first annular shoulder when said king pin is in its lowermost position, an upper bushing seated in said bore above said piston and supporting said king pin for axial and rotative movement relative to said swivel bracket, said upper bushing having a bore receiving said upper king pin portion and an external groove communicating with said bore below said upper bushing, means providing a seal between said upper bushing and said bore, means providing a seal between said king pin and said upper bushing, a lower bushIng seated in said bore below said piston and against said second annular shoulder and supporting said king pin for axial and rotative movement relative to said swivel bracket, said lower bushing having a bore receiving said lower king pin portion and means defining an external recessed area along the upper outer periphery of said lower bushing, means providing a seal between said lower bushing and said bore, means providing a seal between said king pin and said lower bushing, an upper hydraulic conduit extending through said swivel bracket and communicating with said external groove in said upper bushing, a lower hydraulic conduit extending through said swivel bracket and communicating with said recessed area defined by said lower bushing, and an electrically powered reversible combination motor-pump unit communicating with said conduits for selectively supplying hydraulic fluid to said bore through one of said conduits and simultaneously draining hydraulic fluid from said bore through the other of said conduits. 